Secondary battery and top insulator for secondary battery

Abstract

To solve the above problem, a top insulator for a case of a secondary battery, according to an embodiment of the present invention includes: a glass fiber including crossed weft yarns and warp yarns of raw yarns of the glass fiber; and silicone rubber on at least one surface of the glass fiber.

The invention claimed is: 
     
       1. A top insulator for a case of a secondary battery, the top insulator comprising:
 a glass fiber including crossed weft yarns and warp yarns of glass fiber raw yarns; and 
 a silicone rubber on at least one surface of the glass fiber, 
 wherein the glass fiber has a composition ratio in the top insulator of 70% wt to 80% wt, and the silicone rubber has a composition ratio in the top insulator of 20 wt % to 30 wt %, and 
 wherein the silicone rubber comprises a silicone polymer mixed with a flame retardant such that the silicone polymer has a composition ratio in the top insulator of 10 wt % to 20 wt %, and the flame retardant has a composition ratio in the top insulator of 10 wt % to 15 wt %. 
 
     
     
       2. The top insulator of  claim 1 , wherein the silicone rubber comprises:
 a first silicone rubber attached to the glass fiber raw yarns; and 
 a second silicone rubber in a pore between the glass fiber raw yarns. 
 
     
     
       3. The top insulator of  claim 2 , wherein the glass fiber raw yarns cross each other in a shape in which the glass fiber raw yarns are perpendicular to each other, and
 wherein the second silicone rubber is in the pore between the glass fiber raw yarns that are perpendicular to each other. 
 
     
     
       4. The top insulator of  claim 2 , wherein the top insulator has a same thickness as the glass fiber. 
     
     
       5. The top insulator of  claim 1 , wherein the silicone rubber comprises:
 a first silicone rubber applied to at least one surface of the glass fiber; and 
 a second silicone rubber applied to the first silicone rubber. 
 
     
     
       6. The top insulator of  claim 5 , wherein the first silicone rubber is stacked on at least one surface of the glass fiber, and
 wherein the second silicone rubber is stacked on the first silicone rubber. 
 
     
     
       7. The top insulator of  claim 1 , wherein the silicone rubber is stacked on at least one surface of the glass fiber. 
     
     
       8. The top insulator of  claim 1 , wherein the glass fiber has a disc shape. 
     
     
       9. The top insulator of  claim 1 , wherein the silicone rubber is applied to all surfaces of the glass fiber. 
     
     
       10. The top insulator of  claim 1 , wherein the silicone rubber further comprises a pigment. 
     
     
       11. The top insulator of  claim 10 , wherein the pigment has a composition ratio in the top insulator of 5 wt % or less. 
     
     
       12. A secondary battery, comprising:
 a cylindrical battery can; 
 an electrode assembly in the battery can; 
 a cap assembly coupled to an upper portion of the battery can; 
 a beading part provided on a front end of the battery can to mount the cap assembly; 
 a crimping part configured to seal the battery can; and 
 an insulator configured to insulate the electrode assembly, 
 wherein the insulator comprises:
 a glass fiber which including crossed weft yarns and warp yarns of glass fiber raw yarns; and 
 a silicone rubber on at least one surface of the glass fiber, 
 
 wherein the glass fiber has a composition ratio in the top insulator of 70% wt to 80% wt, and the silicone rubber has a composition ratio in the top insulator of 20 wt % to 30 wt %, and 
 wherein the silicone rubber comprises a silicone polymer mixed with a flame retardant such that the silicone polymer has a composition ratio in the top insulator of 10 wt % to 20 wt %, and the flame retardant has a composition ratio in the top insulator of 10 wt % to 15 wt %. 
 
     
     
       13. The secondary battery of  claim 12 , wherein the insulator comprises a top insulator between the electrode assembly and the cap assembly. 
     
     
       14. The secondary battery of  claim 12 , wherein the insulator comprises a bottom insulator between the electrode assembly and a bottom part of the battery can. 
     
     
       15. The secondary battery of  claim 12 , wherein the silicone rubber comprises:
 a first silicone rubber attached to the glass fiber raw yarns; and 
 a second silicone rubber in a pore between the glass fiber raw yarns. 
 
     
     
       16. The secondary battery of  claim 15 , wherein the glass fiber raw yarns cross each other in a shape in which the glass fiber raw yarns are perpendicular to each other, and
 wherein the second silicone rubber is in the pore between the glass fiber raw yarns that are perpendicular to each other. 
 
     
     
       17. The secondary battery of  claim 12 , wherein the silicone rubber comprises a first silicone rubber applied to at least one surface of the glass fiber, and a second silicone rubber applied to the first silicone rubber,
 wherein the first silicone rubber is stacked on at least one surface of the glass fiber, and 
 wherein the second silicone rubber is stacked on the first silicone rubber.